Commercial and scientific notes on essential oils. 9 



100 c. c. of tar, which acid is soluble in cold water. Every 100 c. c. of tar contain 10.3 

 to 12.8 grams of constituents soluble in 5 per cent, soda lye, precipitable by means 

 of hydrochloric acid and soluble again in ether. 



Bay Oil. — According to Robson 1 ), Curator, Montserrat, the results from the bay 

 tree experiment plot in 1919 were more favourable than ever. Although fifty-two 

 distillations were made of leaves reaped from the plot, it was not possible to deal in 

 the still at the Botanic Station with the total quantity reaped, and therefore 1255 lbs. 

 were sold to a distiller at the close of the year. Several thousand pounds of leaves 

 were left unreaped on account of the unability to deal with them. Once the trees 

 are sufficiently developed actually to cover the ground occupied, less and less culti- 

 vation is required. The average yield of oil per 100 lbs. of green leaves in this season 

 on the whole of the distillations was 17.3 ozs., compared with an average of 18.6 in 

 the previous year. The best average results have been obtained between January and 

 July. This, however, may be entirely due to the effect of the usual dry weather at 

 this time of the year, and to the leaves having a reduced water content as the result 

 of evaporation. On the question of the quality of the oil as indicated by the specific 

 gravity and the phenol content, the best results in 1917 were obtained in March, April 

 and May; in 1918, in June and July; and in 1919, in the month of October. A trial 

 was made with old leaves, many of which had been on the trees for at least two 

 years, but the result was disappointing in every respect. 



A bay oil from Mexico may be mentioned here just for the sake of its particular 

 origin. It was only slightly inferior in quality to good West Indian oils: — d i5 o 0.9658, 

 a D — 1°50', n D20O 1.50891, soluble in 0.5 vol. of 80 per cent, alcohol. A further addition 

 of alcohol caused opalescence. The eugenol content, determined with the aid of 

 3 per cent, soda lye, was 55 per cent. 



Birch Tar Oil. — Our repeated endeavours to procure at least small quantities 

 of this product, which originates exclusively from Russia, having failed, it was im- 

 possible so far to satisfy the demand for this oil, so indispensible for the manufacture 

 of a good Russian leather perfume. It is quite understandable, however, that the 

 disastrous economic conditions of that country imply that all attention be directed 

 for the time being to more important products, ~so that the users of the article must 

 wait patiently still longer. 



J. Pritzker and R. Jungkunz 2 ) publish an article on the investigation of the oils of 

 birch tar and other wood tars. From the review of previous publications, given by 

 the authors, it results that the indications regarding the definition of birch tar and 

 the parts of the tree used for its manufacture differ considerably. Some say, it is 

 obtained from the bark; others, from bark and twigs, or from the roots, from the 

 wood, etc. The authors failed in their attempts to obtain absolutely pure birch tar. 

 The results of their investigations show great differences, especially with regard to 

 the indices of refraction, which vary between 50.9 and above 100. However, they 

 afford some general information, which may be useful for further tests of birch tar oils. 



A product styled „Russian leather fat" (birch tar oil), repeatedly offered in Switzer- 

 land, resulted to be a strongly rancid fat, perfumed with some artificial aromatic. 

 Two other birch tar oils were strongly adulterated (more than 50 per cent.) with mineral 



: ) Chemist and Druggist 1)5(1921), 350. — 2 ) Schweiz. Wochenschrif % f. Chem. u. Pharm. 59 (1921), 146, 162. 



